Models of dynamical systems are of great importance in almost all fields of science and engineering and specifically in control, signal processing and information science. Most systems encountered in the real world are nonlinear and in many practical applications nonlinear models are required to achieve an adequate modeling accuracy. A model is always only an approximation of a real phenomenon so that having an approximation theory which allows for the analysis of model quality is a substantial concern.
Wavelet theory has been extensively studied in recent years, and has found many applications in various areas throughout science and engineering, such as numerical analysis and signal processing. Wavelets can capture the local behavior of signals both in frequency and time.